It has been proposed to implement central dictation systems or dictation systems for small work groups by utilizing a number of personal computers that are connected to each other by a data communication network such as a local area network (LAN). Such dictation systems use the well known capabilities now included in most personal computers for recording voice information inputted into the personal computer by a microphone which is connected to the personal computer. Typically, such microphones are connected to a “sound card” which is a standard component of many types of personal computer. (The term “personal computer” should be understood to include all of the computing devices, whether portable or desktop, which operate with the Windows or Macintosh or other well-known operating systems, and are used for office applications such as word-processing or financial spreadsheets.)
A dictation system implemented with networked personal computers is described in co-pending patent application Ser. No. 09/099,501, which has common inventors and a common assignee with the present application. Computer software, hand microphones and foot-pedals used to adapt a personal computer network to operate as a dictation system are commercially available from the assignee of the present application under the trademark “Boomerang”.
A hand microphone suitable for connection to a personal computer as part of the Boomerang system is described in the above-referenced '501 patent application. The hand, microphone disclosed therein resembles, in its physical appearance hand microphones which are conventionally interfaced to desktop dictation tape recorders. The hand microphone includes a voice input microphone, a speaker, and a number of manually-actuatable function control switches. All of these components are installed in or on a compact housing which is shaped and sized to be held conveniently in the user's hand. Also installed within the housing is a microprocessor which receives and interprets control signals generated by the control switches and transmits suitable control signals to the personal computer via a data communication channel.
Although the hand microphone disclosed in the '501 patent application operates very satisfactorily for its intended purpose, it would be desirable to reduce the cost of the hand microphone while preserving most or all of its functions.
It has also been proposed to provide a hand microphone that is interfaced to a personal computer for the purpose of controlling dictation operations, wherein the hand microphone provides an analog signal level to a game port or other suitable receptacle of the personal computer. However, known hand microphones which provide an analog signal level are limited in the number of different control functions that the microphone supports, and also may fail to generate control signals with sufficient precision to prevent malfunctions.